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src/compare/util.rs

@@ -141,6 +141,11 @@ fn maybe_token_to_usize(
         .map_or(Ok(None), |r| r.map(Some))?)
 }
 
+/// Get a named property from the emacs token.
+///
+/// Returns Ok(None) if value is nil.
+///
+/// Returns error if the attribute is not specified on the token at all.
 pub fn get_property<'s, 'x>(
     emacs: &'s Token<'s>,
     key: &'x str,